Gas flares are commonly located at production facilities, refineries, processing plants, and the like for disposing of combustible waste gases and other combustible gas streams that are diverted due to venting requirements, shut-downs, upsets, and/or emergencies. Such flares are often operated in a smokeless or near smokeless manner, which can be largely achieved by making sure that the flammable gas to be discharged and burned (“flare gas”) is admixed with enough air to sufficiently oxidize the gas.
A typical flare apparatus includes one or more flare burners and a pilot. As gases exit the flare burners, the gases mix with the oxygen and combust (via the flame from the pilot). Some flare burners use various methods in an attempt to provide sufficient oxygen in a combustion zone of a flare burner to help minimize the formation of smoke.
For example, in some flare burners, the size of the flare burner is larger. However, as a result of the large size of the flare burner, a significant amount of ground space is often required for the flare burner. This problem is increased when multiple flare burners are used, with the burner array requiring a large area of ground space.
In some flare burners, the flame that is produced is very high. Not only is the high flame height undesirable, but the high flame height requires a higher fence around the flare burner area. The higher fence is more expensive. The higher flow of waste gas in the center of the flare tip can also increase the oxygen requirements at the center of the flare tip. This can increase the propensity of the flare to smoke.
Furthermore, many large flare burner areas require a large amount of piping and multiple valves. The required piping and valves increase the capital cost associated with the flare burner. Additionally, these types of flare burners also may require welded joints and attachment points. This results in a flare burner that is complex to assemble and costs more.
Finally, many flare burners are noisy mainly due to both jet noise and combustion noise. While the jet noise (the noise associated with the speed of the gases exiting the burner) may not be able to be lowered, it is believed that the combustion noise (associated with the mixing of the air and fuel gases) can be lowered and still provide an acceptable flame.
Therefore, it would be desirable to have a flare burner for combustible gas that addresses at least one of these issues.